AVRCP MediaBrowserService support ACTION_PREPARE

Report support for ACTION_PREPARE when connected to a bluetooth device
capable of streaming.

Bug: 141469207
Test: dumpsys media_session reports ACTION_PREPARE in actions
Change-Id: I43702ba629750c02411cd39a1211bb352cc7457b
(cherry picked from commit fa4bcf35)

Merged-In: I43702ba629750c02411cd39a1211bb352cc7457b
Change-Id: I09cb56e8f59dfa15faea6581f379c06665076a63